drivers/hwmon/ibmpowernv.c - linux - Git at Google

 /*
  * IBM PowerNV platform sensors for temperature/fan/voltage/power
  * Copyright (C) 2014 IBM
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program.
  */

 #define DRVNAME		"ibmpowernv"
 #define pr_fmt(fmt)	DRVNAME ": " fmt

 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/of.h>
 #include <linux/slab.h>

 #include <linux/platform_device.h>
 #include <asm/opal.h>
 #include <linux/err.h>

 #define MAX_ATTR_LEN	32

 /* Sensor suffix name from DT */
 #define DT_FAULT_ATTR_SUFFIX		"faulted"
 #define DT_DATA_ATTR_SUFFIX		"data"
 #define DT_THRESHOLD_ATTR_SUFFIX	"thrs"

 /*
  * Enumerates all the types of sensors in the POWERNV platform and does index
  * into 'struct sensor_group'
  */
 enum sensors {
 	FAN,
 	AMBIENT_TEMP,
 	POWER_SUPPLY,
 	POWER_INPUT,
 	MAX_SENSOR_TYPE,
 };

 static struct sensor_group {
 	const char *name;
 	const char *compatible;
 	struct attribute_group group;
 	u32 attr_count;
 } sensor_groups[] = {
 	{"fan", "ibm,opal-sensor-cooling-fan"},
 	{"temp", "ibm,opal-sensor-amb-temp"},
 	{"in", "ibm,opal-sensor-power-supply"},
 	{"power", "ibm,opal-sensor-power"}
 };

 struct sensor_data {
 	u32 id; /* An opaque id of the firmware for each sensor */
 	enum sensors type;
 	char name[MAX_ATTR_LEN];
 	struct device_attribute dev_attr;
 };

 struct platform_data {
 	const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
 	u32 sensors_count; /* Total count of sensors from each group */
 };

 /* Platform device representing all the ibmpowernv sensors */
 static struct platform_device *pdevice;

 static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
 			   char *buf)
 {
 	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
 						 dev_attr);
 	ssize_t ret;
 	u32 x;

 	ret = opal_get_sensor_data(sdata->id, &x);
 	if (ret)
 		return ret;

 	/* Convert temperature to milli-degrees */
 	if (sdata->type == AMBIENT_TEMP)
 		x *= 1000;
 	/* Convert power to micro-watts */
 	else if (sdata->type == POWER_INPUT)
 		x *= 1000000;

 	return sprintf(buf, "%u\n", x);
 }

 static int __init get_sensor_index_attr(const char *name, u32 *index,
 					char *attr)
 {
 	char *hash_pos = strchr(name, '#');
 	char buf[8] = { 0 };
 	char *dash_pos;
 	u32 copy_len;
 	int err;

 	if (!hash_pos)
 		return -EINVAL;

 	dash_pos = strchr(hash_pos, '-');
 	if (!dash_pos)
 		return -EINVAL;

 	copy_len = dash_pos - hash_pos - 1;
 	if (copy_len >= sizeof(buf))
 		return -EINVAL;

 	strncpy(buf, hash_pos + 1, copy_len);

 	err = kstrtou32(buf, 10, index);
 	if (err)
 		return err;

 	strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);

 	return 0;
 }

 /*
  * This function translates the DT node name into the 'hwmon' attribute name.
  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
  * which need to be mapped as fan2_input, temp1_max respectively before
  * populating them inside hwmon device class.
  */
 static int __init create_hwmon_attr_name(struct device *dev, enum sensors type,
 					 const char *node_name,
 					 char *hwmon_attr_name)
 {
 	char attr_suffix[MAX_ATTR_LEN];
 	char *attr_name;
 	u32 index;
 	int err;

 	err = get_sensor_index_attr(node_name, &index, attr_suffix);
 	if (err) {
 		dev_err(dev, "Sensor device node name '%s' is invalid\n",
 			node_name);
 		return err;
 	}

 	if (!strcmp(attr_suffix, DT_FAULT_ATTR_SUFFIX)) {
 		attr_name = "fault";
 	} else if (!strcmp(attr_suffix, DT_DATA_ATTR_SUFFIX)) {
 		attr_name = "input";
 	} else if (!strcmp(attr_suffix, DT_THRESHOLD_ATTR_SUFFIX)) {
 		if (type == AMBIENT_TEMP)
 			attr_name = "max";
 		else if (type == FAN)
 			attr_name = "min";
 		else
 			return -ENOENT;
 	} else {
 		return -ENOENT;
 	}

 	snprintf(hwmon_attr_name, MAX_ATTR_LEN, "%s%d_%s",
 		 sensor_groups[type].name, index, attr_name);
 	return 0;
 }

 static int __init populate_attr_groups(struct platform_device *pdev)
 {
 	struct platform_data *pdata = platform_get_drvdata(pdev);
 	const struct attribute_group **pgroups = pdata->attr_groups;
 	struct device_node *opal, *np;
 	enum sensors type;

 	opal = of_find_node_by_path("/ibm,opal/sensors");
 	if (!opal) {
 		dev_err(&pdev->dev, "Opal node 'sensors' not found\n");
 		return -ENODEV;
 	}

 	for_each_child_of_node(opal, np) {
 		if (np->name == NULL)
 			continue;

 		for (type = 0; type < MAX_SENSOR_TYPE; type++)
 			if (of_device_is_compatible(np,
 					sensor_groups[type].compatible)) {
 				sensor_groups[type].attr_count++;
 				break;
 			}
 	}

 	of_node_put(opal);

 	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
 		sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
 					sizeof(struct attribute *) *
 					(sensor_groups[type].attr_count + 1),
 					GFP_KERNEL);
 		if (!sensor_groups[type].group.attrs)
 			return -ENOMEM;

 		pgroups[type] = &sensor_groups[type].group;
 		pdata->sensors_count += sensor_groups[type].attr_count;
 		sensor_groups[type].attr_count = 0;
 	}

 	return 0;
 }

 /*
  * Iterate through the device tree for each child of 'sensors' node, create
  * a sysfs attribute file, the file is named by translating the DT node name
  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
  * etc..
  */
 static int __init create_device_attrs(struct platform_device *pdev)
 {
 	struct platform_data *pdata = platform_get_drvdata(pdev);
 	const struct attribute_group **pgroups = pdata->attr_groups;
 	struct device_node *opal, *np;
 	struct sensor_data *sdata;
 	const __be32 *sensor_id;
 	enum sensors type;
 	u32 count = 0;
 	int err = 0;

 	opal = of_find_node_by_path("/ibm,opal/sensors");
 	sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
 			     GFP_KERNEL);
 	if (!sdata) {
 		err = -ENOMEM;
 		goto exit_put_node;
 	}

 	for_each_child_of_node(opal, np) {
 		if (np->name == NULL)
 			continue;

 		for (type = 0; type < MAX_SENSOR_TYPE; type++)
 			if (of_device_is_compatible(np,
 					sensor_groups[type].compatible))
 				break;

 		if (type == MAX_SENSOR_TYPE)
 			continue;

 		sensor_id = of_get_property(np, "sensor-id", NULL);
 		if (!sensor_id) {
 			dev_info(&pdev->dev,
 				 "'sensor-id' missing in the node '%s'\n",
 				 np->name);
 			continue;
 		}

 		sdata[count].id = be32_to_cpup(sensor_id);
 		sdata[count].type = type;
 		err = create_hwmon_attr_name(&pdev->dev, type, np->name,
 					     sdata[count].name);
 		if (err)
 			goto exit_put_node;

 		sysfs_attr_init(&sdata[count].dev_attr.attr);
 		sdata[count].dev_attr.attr.name = sdata[count].name;
 		sdata[count].dev_attr.attr.mode = S_IRUGO;
 		sdata[count].dev_attr.show = show_sensor;

 		pgroups[type]->attrs[sensor_groups[type].attr_count++] =
 				&sdata[count++].dev_attr.attr;
 	}

 exit_put_node:
 	of_node_put(opal);
 	return err;
 }

 static int __init ibmpowernv_probe(struct platform_device *pdev)
 {
 	struct platform_data *pdata;
 	struct device *hwmon_dev;
 	int err;

 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 	if (!pdata)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, pdata);
 	pdata->sensors_count = 0;
 	err = populate_attr_groups(pdev);
 	if (err)
 		return err;

 	/* Create sysfs attribute data for each sensor found in the DT */
 	err = create_device_attrs(pdev);
 	if (err)
 		return err;

 	/* Finally, register with hwmon */
 	hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
 							   pdata,
 							   pdata->attr_groups);

 	return PTR_ERR_OR_ZERO(hwmon_dev);
 }

 static struct platform_driver ibmpowernv_driver = {
 	.driver = {
 		.owner = THIS_MODULE,
 		.name = DRVNAME,
 	},
 };

 static int __init ibmpowernv_init(void)
 {
 	int err;

 	pdevice = platform_device_alloc(DRVNAME, 0);
 	if (!pdevice) {
 		pr_err("Device allocation failed\n");
 		err = -ENOMEM;
 		goto exit;
 	}

 	err = platform_device_add(pdevice);
 	if (err) {
 		pr_err("Device addition failed (%d)\n", err);
 		goto exit_device_put;
 	}

 	err = platform_driver_probe(&ibmpowernv_driver, ibmpowernv_probe);
 	if (err) {
 		pr_err("Platfrom driver probe failed\n");
 		goto exit_device_del;
 	}

 	return 0;

 exit_device_del:
 	platform_device_del(pdevice);
 exit_device_put:
 	platform_device_put(pdevice);
 exit:
 	return err;
 }

 static void __exit ibmpowernv_exit(void)
 {
 	platform_driver_unregister(&ibmpowernv_driver);
 	platform_device_unregister(pdevice);
 }

 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
 MODULE_LICENSE("GPL");

 module_init(ibmpowernv_init);
 module_exit(ibmpowernv_exit);
	/*
	* IBM PowerNV platform sensors for temperature/fan/voltage/power
	* Copyright (C) 2014 IBM
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program.
	*/

	#define DRVNAME "ibmpowernv"
	#define pr_fmt(fmt) DRVNAME ": " fmt

	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/hwmon.h>
	#include <linux/hwmon-sysfs.h>
	#include <linux/of.h>
	#include <linux/slab.h>

	#include <linux/platform_device.h>
	#include <asm/opal.h>
	#include <linux/err.h>

	#define MAX_ATTR_LEN 32

	/* Sensor suffix name from DT */
	#define DT_FAULT_ATTR_SUFFIX "faulted"
	#define DT_DATA_ATTR_SUFFIX "data"
	#define DT_THRESHOLD_ATTR_SUFFIX "thrs"

	/*
	* Enumerates all the types of sensors in the POWERNV platform and does index
	* into 'struct sensor_group'
	*/
	enum sensors {
	FAN,
	AMBIENT_TEMP,
	POWER_SUPPLY,
	POWER_INPUT,
	MAX_SENSOR_TYPE,
	};

	static struct sensor_group {
	const char *name;
	const char *compatible;
	struct attribute_group group;
	u32 attr_count;
	} sensor_groups[] = {
	{"fan", "ibm,opal-sensor-cooling-fan"},
	{"temp", "ibm,opal-sensor-amb-temp"},
	{"in", "ibm,opal-sensor-power-supply"},
	{"power", "ibm,opal-sensor-power"}
	};

	struct sensor_data {
	u32 id; /* An opaque id of the firmware for each sensor */
	enum sensors type;
	char name[MAX_ATTR_LEN];
	struct device_attribute dev_attr;
	};

	struct platform_data {
	const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
	u32 sensors_count; /* Total count of sensors from each group */
	};

	/* Platform device representing all the ibmpowernv sensors */
	static struct platform_device *pdevice;

	static ssize_t show_sensor(struct device dev, struct device_attribute devattr,
	char *buf)
	{
	struct sensor_data *sdata = container_of(devattr, struct sensor_data,
	dev_attr);
	ssize_t ret;
	u32 x;

	ret = opal_get_sensor_data(sdata->id, &x);
	if (ret)
	return ret;

	/* Convert temperature to milli-degrees */
	if (sdata->type == AMBIENT_TEMP)
	x *= 1000;
	/* Convert power to micro-watts */
	else if (sdata->type == POWER_INPUT)
	x *= 1000000;

	return sprintf(buf, "%u\n", x);
	}

	static int __init get_sensor_index_attr(const char name, u32 index,
	char *attr)
	{
	char *hash_pos = strchr(name, '#');
	char buf[8] = { 0 };
	char *dash_pos;
	u32 copy_len;
	int err;

	if (!hash_pos)
	return -EINVAL;

	dash_pos = strchr(hash_pos, '-');
	if (!dash_pos)
	return -EINVAL;

	copy_len = dash_pos - hash_pos - 1;
	if (copy_len >= sizeof(buf))
	return -EINVAL;

	strncpy(buf, hash_pos + 1, copy_len);

	err = kstrtou32(buf, 10, index);
	if (err)
	return err;

	strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);

	return 0;
	}

	/*
	* This function translates the DT node name into the 'hwmon' attribute name.
	* IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
	* which need to be mapped as fan2_input, temp1_max respectively before
	* populating them inside hwmon device class.
	*/
	static int __init create_hwmon_attr_name(struct device *dev, enum sensors type,
	const char *node_name,
	char *hwmon_attr_name)
	{
	char attr_suffix[MAX_ATTR_LEN];
	char *attr_name;
	u32 index;
	int err;

	err = get_sensor_index_attr(node_name, &index, attr_suffix);
	if (err) {
	dev_err(dev, "Sensor device node name '%s' is invalid\n",
	node_name);
	return err;
	}

	if (!strcmp(attr_suffix, DT_FAULT_ATTR_SUFFIX)) {
	attr_name = "fault";
	} else if (!strcmp(attr_suffix, DT_DATA_ATTR_SUFFIX)) {
	attr_name = "input";
	} else if (!strcmp(attr_suffix, DT_THRESHOLD_ATTR_SUFFIX)) {
	if (type == AMBIENT_TEMP)
	attr_name = "max";
	else if (type == FAN)
	attr_name = "min";
	else
	return -ENOENT;
	} else {
	return -ENOENT;
	}

	snprintf(hwmon_attr_name, MAX_ATTR_LEN, "%s%d_%s",
	sensor_groups[type].name, index, attr_name);
	return 0;
	}

	static int __init populate_attr_groups(struct platform_device *pdev)
	{
	struct platform_data *pdata = platform_get_drvdata(pdev);
	const struct attribute_group **pgroups = pdata->attr_groups;
	struct device_node opal, np;
	enum sensors type;

	opal = of_find_node_by_path("/ibm,opal/sensors");
	if (!opal) {
	dev_err(&pdev->dev, "Opal node 'sensors' not found\n");
	return -ENODEV;
	}

	for_each_child_of_node(opal, np) {
	if (np->name == NULL)
	continue;

	for (type = 0; type < MAX_SENSOR_TYPE; type++)
	if (of_device_is_compatible(np,
	sensor_groups[type].compatible)) {
	sensor_groups[type].attr_count++;
	break;
	}
	}

	of_node_put(opal);

	for (type = 0; type < MAX_SENSOR_TYPE; type++) {
	sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
	sizeof(struct attribute )
	(sensor_groups[type].attr_count + 1),
	GFP_KERNEL);
	if (!sensor_groups[type].group.attrs)
	return -ENOMEM;

	pgroups[type] = &sensor_groups[type].group;
	pdata->sensors_count += sensor_groups[type].attr_count;
	sensor_groups[type].attr_count = 0;
	}

	return 0;
	}

	/*
	* Iterate through the device tree for each child of 'sensors' node, create
	* a sysfs attribute file, the file is named by translating the DT node name
	* to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
	* etc..
	*/
	static int __init create_device_attrs(struct platform_device *pdev)
	{
	struct platform_data *pdata = platform_get_drvdata(pdev);
	const struct attribute_group **pgroups = pdata->attr_groups;
	struct device_node opal, np;
	struct sensor_data *sdata;
	const __be32 *sensor_id;
	enum sensors type;
	u32 count = 0;
	int err = 0;

	opal = of_find_node_by_path("/ibm,opal/sensors");
	sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
	GFP_KERNEL);
	if (!sdata) {
	err = -ENOMEM;
	goto exit_put_node;
	}

	for_each_child_of_node(opal, np) {
	if (np->name == NULL)
	continue;

	for (type = 0; type < MAX_SENSOR_TYPE; type++)
	if (of_device_is_compatible(np,
	sensor_groups[type].compatible))
	break;

	if (type == MAX_SENSOR_TYPE)
	continue;

	sensor_id = of_get_property(np, "sensor-id", NULL);
	if (!sensor_id) {
	dev_info(&pdev->dev,
	"'sensor-id' missing in the node '%s'\n",
	np->name);
	continue;
	}

	sdata[count].id = be32_to_cpup(sensor_id);
	sdata[count].type = type;
	err = create_hwmon_attr_name(&pdev->dev, type, np->name,
	sdata[count].name);
	if (err)
	goto exit_put_node;

	sysfs_attr_init(&sdata[count].dev_attr.attr);
	sdata[count].dev_attr.attr.name = sdata[count].name;
	sdata[count].dev_attr.attr.mode = S_IRUGO;
	sdata[count].dev_attr.show = show_sensor;

	pgroups[type]->attrs[sensor_groups[type].attr_count++] =
	&sdata[count++].dev_attr.attr;
	}

	exit_put_node:
	of_node_put(opal);
	return err;
	}

	static int __init ibmpowernv_probe(struct platform_device *pdev)
	{
	struct platform_data *pdata;
	struct device *hwmon_dev;
	int err;

	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
	return -ENOMEM;

	platform_set_drvdata(pdev, pdata);
	pdata->sensors_count = 0;
	err = populate_attr_groups(pdev);
	if (err)
	return err;

	/* Create sysfs attribute data for each sensor found in the DT */
	err = create_device_attrs(pdev);
	if (err)
	return err;

	/* Finally, register with hwmon */
	hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
	pdata,
	pdata->attr_groups);

	return PTR_ERR_OR_ZERO(hwmon_dev);
	}

	static struct platform_driver ibmpowernv_driver = {
	.driver = {
	.owner = THIS_MODULE,
	.name = DRVNAME,
	},
	};

	static int __init ibmpowernv_init(void)
	{
	int err;

	pdevice = platform_device_alloc(DRVNAME, 0);
	if (!pdevice) {
	pr_err("Device allocation failed\n");
	err = -ENOMEM;
	goto exit;
	}

	err = platform_device_add(pdevice);
	if (err) {
	pr_err("Device addition failed (%d)\n", err);
	goto exit_device_put;
	}

	err = platform_driver_probe(&ibmpowernv_driver, ibmpowernv_probe);
	if (err) {
	pr_err("Platfrom driver probe failed\n");
	goto exit_device_del;
	}

	return 0;

	exit_device_del:
	platform_device_del(pdevice);
	exit_device_put:
	platform_device_put(pdevice);
	exit:
	return err;
	}

	static void __exit ibmpowernv_exit(void)
	{
	platform_driver_unregister(&ibmpowernv_driver);
	platform_device_unregister(pdevice);
	}

	MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
	MODULE_DESCRIPTION("IBM POWERNV platform sensors");
	MODULE_LICENSE("GPL");

	module_init(ibmpowernv_init);
	module_exit(ibmpowernv_exit);